The notion that Donald Trump is some new phenomenon on the political scene is sadly mistaken. Would that he were. His type has been seen before -- all over Latin America, which may explain why the United States has prospered, and even remained a republic, while much of the rest of the continent has seen dictatorships come and go.

Just abandon the foundations of republican government -- like the rule of law under an independent judiciary -- and there's little to prevent our becoming a banana republic too. Our current president toys with ruling by executive decree every time Congress refuses to do his bidding. And begins imitating those Latin American strongmen who turn out to be weak indeed. It can be a popular move -- till the people catch on. But we're told desperate times require desperate measures. Even if these times are scarcely desperate. As calmer heads like Warren Buffet keep saying.

Even the longest-running democracies aren't immune to fits of hysteria. There was a time when Venezuela, too, was a stable republic. But when its economy soured and corruption grew rampant, a caudillo appeared, promising to restore its old stability. He didn't. He only made things infinitely worse.

Ditto the Perons in Argentina, which is still struggling to recover from their misrule. It may be hard to remember now, but there was a time when Argentina was the breadbasket of the New World, attracting investment and industrious immigrants from all over the world. But it isn't now that a succession of little Mussolinis have had their way with it.

And now Donald Trump promises to perform the same disservice for this country.

The same tactics have been tried here before, too -- by Aaron Burr in the still early days of this republic, which remained one, no thanks to him. Popularity, as evinced by landslide electoral victories, also tend to turn our own leaders' heads. After his party swept the country in 1936, Franklin Roosevelt set out to pack the Supreme Court, and though he failed, it wasn't by much.

The price of republican government remains eternal vigilance -- and a sense of restraint on the part of even and especially the most popular leaders. Else, we're inviting the reign of the Donald Trumps.